The first observation of the doubly charmed baryon $\\it{\\Xi}_{cc}^+$ is reported through its decay to the $\\it{\\Lambda}_c^+ K^-\\pi^+$ final state, with a statistical significance exceeding seven standard deviations. The observation is made using proton-proton collision data collected in 2024 with the LHCb Run 3 detector at a center-of-mass energy of 13.6 TeV, corresponding to a total integrated luminosity of $6.9\\,\\mathrm{fb}^{-1}$. The $\\it{\\Xi}_{cc}^+$ mass is measured to be $3619.97 \\pm 0.83 \\pm 0.26^{+1.90}_{-1.30}\\mathrm{MeV}\/c^2$, where the first uncertainty is statistical, the second is systematic, and the third is due to the unknown $\\it{\\Xi}_{cc}^+$ lifetime, which is assumed to lie in the range 15-160 fs with a baseline value of 45 fs. The difference between the masses of the $\\it{\\Xi}_{cc}^+$ and $\\it{\\Xi}_{cc}^{++}$ baryons is determined to be $-1.77 \\pm 0.84 \\pm 0.15^{+1.90}_{-1.30}\\mathrm{MeV}\/c^2$. This is the first observation of a new particle made with the LHCb Run 3 detector.<\/p>\n","protected":false},"excerpt":{"rendered":"
The first observation of the doubly charmed baryon $\\it{\\Xi}_{cc}^+$ is reported through its decay to the $\\it{\\Lambda}_c^+ K^-\\pi^+$ final state, with a statistical significance exceeding seven standard deviations. The observation is made using proton-proton collision data collected in 2024 with the LHCb Run 3 detector at a center-of-mass energy of 13.6 TeV, corresponding to a total integrated luminosity of $6.9\\,\\mathrm{fb}^{-1}$. The $\\it{\\Xi}_{cc}^+$ mass is measured to be $3619.97 \\pm 0.83 […]<\/p>\n","protected":false},"author":12,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"publication-type":[30],"class_list":["post-36553","publication","type-publication","status-publish","hentry","publication-type-article"],"acf":[],"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/36553","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication"}],"about":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/types\/publication"}],"author":[{"embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/users\/12"}],"version-history":[{"count":0,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/36553\/revisions"}],"wp:attachment":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/media?parent=36553"}],"wp:term":[{"taxonomy":"publication-type","embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication-type?post=36553"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}